Electric washing machine

ABSTRACT

An electric washing machine according to the present invention performs a washing process for washing laundry without the use of a detergent by generating water streams in an outer tub ( 2 ) containing an electrolyzed liquid produced through electrolysis by an electrolyzing device ( 31 ) when a zero detergent course is selected by a user. The electrolyzing device ( 31 ) is provided as a water treatment unit ( 60 ) attached to a lower portion of an outer side surface ( 66 ) of the outer tub ( 2 ), and includes a thin-box-shaped electrolyzing chamber ( 32 ), a pair of electrodes ( 33 ) supported at opposite edges thereof, and a pair of water communication paths ( 34, 35 ). The pair of water communication paths ( 34, 35 ) are disposed in a vertically juxtaposed relation to connect the outer tub ( 2 ) to the electrolyzing chamber ( 32 ) with the intervention of packings ( 81 ). Thus, an assembling operation and the like can conveniently be performed, and water can efficiently be electrolyzed for use in the washing process.

TECHNICAL FIELD

The present invention relates to an electric washing machine.

PRIOR ART

Electric washing machines usually perform a washing process with the useof a detergent.

SUMMARY OF THE INVENTION

It is a main object of the present invention to provide an electricwashing machine which is capable of washing laundry without the use of adetergent.

In accordance with a first aspect of the present invention, there isprovided an electric washing machine comprising: a washing tub forcontaining laundry; water stream generating means for generating waterstreams in the washing tub; water treatment means for performing aspecific treatment on tap water to be supplied into the washing tub ortap water supplied into the washing tub to impart the water with acleaning capability without addition of a detergent; storage means whichstores therein a sequence for a first washing course in which thelaundry is washed by generating water streams in the washing tub whichcontains a detergent solution prepared by adding the detergent into thetap water, and a sequence for a second washing course in which thelaundry is washed without the use of the detergent by generating waterstreams in the washing tub which contains a cleaning liquid impartedwith the cleaning capability by treating the tap water by the watertreatment means; selecting means for allowing a user to select the firstwashing course or the second washing course; and control means forcontrolling operations of the water stream generating means and thewater treatment means on the basis of the sequence for the washingcourse selected by the selecting means to perform a washing process inthe selected washing course.

More specifically, the water treatment means includes a pair ofelectrodes for electrolysis of the tap water, and is adapted to producethe cleaning liquid by electrolyzing the tap water through energizationof the pair of electrodes.

In the aforesaid arrangement, the machine preferably further comprisesload detecting means for detecting a load of the laundry and informationmeans for notifying a detergent amount according to the load detected bythe load detecting means, wherein the control means actuates the loaddetecting means for the detection of the load and causes the informationmeans to notify the detergent amount according to the detected load inthe washing process of the first washing course, and prohibits theinformation means from notifying the detergent amount in the washingprocess of the second washing course.

The machine preferably further comprises second information means fornotifying that no detergent is added, wherein the control means actuatesthe second information means in the washing process of the secondwashing course.

Alternatively, the machine preferably further comprises load detectingmeans for detecting a load of the laundry, and adding means for addingthe detergent in an amount according to the load detected by the loaddetecting means, wherein the control means actuates the load detectingmeans for the detection of the load and causes the adding means to addthe detergent in the amount according to the detected load in thewashing process of the first washing course, and prohibits the addingmeans from adding the detergent in the washing process of the secondwashing course.

In the aforesaid arrangements, where the first washing course isselected by the user, the water streams are generated in the washing tubcontaining the detergent solution (prepared by adding the detergent intothe tap water) for washing the laundry in the washing process. Morespecifically, the load of the laundry contained in the washing tub isdetected. Then, the detergent amount according to the detected load isnotified (by display or voice), and the user adds a proper amount of thedetergent on the basis of the notification. Alternatively, the detergentis automatically added according to the detected load.

A place where the detergent is added is, for example, the washing tub ora detergent box. That is, the place may be where the detergent is mixedwith the water contained in the washing tub.

When the water containing the detergent (detergent solution) iscontained in the washing tub, the water streams are generated forwashing the laundry. Dirt adhering to the laundry is removed by theeffect of the detergent and the effect of the water streams.

Where the second washing course is selected by the user, the waterstreams are generated in the washing tub containing the cleaning liquid(e.g., electrolyzed liquid) produced through the treatment by the watertreatment means for washing the laundry without the use of the detergentin the washing process.

More specifically, the pair of electrodes are disposed in a space wherethe tap water in the washing tub can be electrolyzed, for example, inthe washing tub or a chamber communicating with the washing tub. First,the water is retained in the washing tub. Then, the water in the washingtub is electrolyzed through energization of the pair of electrodes forproduction of the electrolyzed water as the cleaning liquid. In theelectrolyzed water contained in the washing tub, the water streams aregenerated for washing the laundry. In this washing process, theinformation on the detergent amount according to the load is not given,but addition of no detergent is notified. Alternatively, the automaticaddition of the detergent is not effected.

The tap water contains very small amounts of impurities such as iron,calcium, magnesium and chlorine, and the electrolysis thereof providesthe following effects. That is, the electrolyzed water is neutral toalkaline. In addition, active oxygen is generated. Further, hypochlorousacid and hypochlorous ions are generated. Dirt adhering to the laundryis removed by the effect of the alkaline water, the effect of the activeoxygen and the effect of the water streams. In addition, the laundry issterilized by the effect of hypochlorous acid and hypochlorous ions.

The washing operation by the water streams may be performed during thewater treatment (electrolysis), or after the water treatment. Ratherthan the treatment (electrolysis) of the tap water contained in thewashing tub, the water treatment means (the pair of electrodes) may beprovided upstream of the washing tub, so that the tap water is treatedfor the production of the cleaning liquid which is in turn supplied intothe washing tub.

With the aforesaid arrangements, the washing course for washing thelaundry without the use of the detergent can be realized, so that theamount of the detergent to be used can drastically be reduced.

Further, the information on the detergent amount according to the loadis provided in the first washing course employing the detergent, and isnot provided in the second washing course employing no detergent.Therefore, the proper amount of the detergent can be added without anyexcess or shortage in the first washing course, and the use of nodetergent can expressly be notified to prevent the user from mistakenlyadding the detergent in the second washing course employing nodetergent.

In the second washing course, the use of no detergent is notified,thereby assuredly preventing the user from adding the detergent.

The detergent is automatically added in an amount according to the loadin the first washing course employing the detergent, and the automaticaddition of the detergent is not effected in the second washing courseemploying no detergent. Therefore, the proper amount of the detergentcan be added without any excess or shortage in the first washing course,and wasteful use of the detergent can be prevented in the second washingcourse employing no detergent.

In accordance with another aspect of the present invention, there isprovided an electric washing machine which is adapted to selectivelyeffect a first washing course in which laundry is washed with the use ofa detergent and a second washing course in which the laundry is washedin a manner different from the first washing course without the use ofthe detergent.

With the aforesaid arrangement, the washing course for washing thelaundry without the use of the detergent is realized, so that the amountof the detergent to be used can drastically be reduced.

In accordance with further another aspect of the present invention,there is provided an electric washing machine comprising a watertreatment unit for electrolyzing water in use for a washing process toimpart the water with a cleaning capability without addition of adetergent, the water treatment unit being attached to the outside of awashing tub.

Thus, the amount of the detergent to be used can be reduced, and thewater treatment unit can easily be handled from the outside of thewashing tub. Therefore, a mounting operation for mounting the watertreatment unit on the washing tub, a maintenance operation for the watertreatment unit and a disassembling operation for recycling, for example,can be facilitated.

In the aforesaid arrangement, the water treatment unit preferablyincludes an electrolyzing chamber, at least one pair of electrodesdisposed in the electrolyzing chamber, and a pair of water communicationpaths extending from the electrolyzing chamber, the pair of watercommunication paths being connected to the washing tub, wherein thewater flows into the electrolyzing chamber from the washing tub throughone of the water communication paths, and the water treated in theelectrolyzing chamber flows out into the washing tub through the otherwater communication path.

Thus, the water treatment unit can unitarily be handled in theassembling and maintenance operations, so that these operations arefurther facilitated.

Since the pair of water communication paths ensure efficient watercommunication between the electrolyzing chamber and the washing tub, thetreated water can be supplied into the washing tub for efficient use inthe washing process without waste, and the water from the washing tub iscaused to flow within the electrolyzing chamber for efficientelectrolysis.

In the aforesaid arrangement, the electrolyzing chamber preferably has athin box shape having a smaller depth with respect to an outer surfaceof the washing tub, and the electrodes preferably each have a plateshape corresponding to the thin box shape of the electrolyzing chamber.The plate-shaped electrodes are preferably disposed at a predeterminedinter-electrode pitch with opposite edges thereof being supported.

Thus, the projection of the water treatment unit from the outer surfaceof the washing tub can be reduced for space saving.

Since the electrodes are held at the opposite edges thereof in thebox-shaped electrolyzing chamber, the water treatment unit can behandled without careful attention. Therefore, the assembling,maintenance and disassembling operations can be facilitated.

In the aforesaid arrangement, the electrolyzing chamber is preferablymounted on an outer side surface of the washing tub. The one watercommunication path (inlet path) preferably extends from a lower portionof the electrolyzing chamber, and the other water communication path(outlet path) preferably extends from an upper portion of theelectrolyzing chamber. The water communication paths are preferablyconnected to the washing tub with the intervention of packings.

With the use of the packings, dimensional errors can be accommodatedwhen the water treatment unit is mounted on the washing tub, so that themounting can easily be achieved. In addition, sealing of gaps betweenthe water communication paths and the washing tub can be achieved.

Since the pair of water communication paths are provided at differentvertical positions of the thin-box-shaped electrolyzing chamber attachedto the outer side surface of the washing tub, vertical water flow isfacilitated for efficient electrolysis.

In the aforesaid arrangement, the upper portion of the electrolyzingchamber is preferably inclined with one side thereof located at a higherposition, and the outlet path preferably extends from the higherposition. The inlet path preferably extends from a lower end of theelectrolyzing chamber. Thus, the water flow in the electrolyzing chambercan be facilitated.

In the aforesaid arrangement, an air supply port for supplying air ispreferably provided at a lower portion of the electrolyzing chamber,whereby the air supplied into the electrolyzing chamber from the airsupply port flows into the washing tub through the upper watercommunication path, and the water contained in the electrolyzing chamberis caused to flow by the air flow. Thus, the water flow in theelectrolyzing chamber can be facilitated for efficient electrolysis. Inaddition, the air is introduced into the washing tub, therebycontributing to improvement of the cleaning capability.

In the aforesaid arrangement, the air is preferably supplied withoutcontact with the electrodes. Thus, reduction in electrolysis efficiencydue to the air can be suppressed.

In the aforesaid arrangement, the electrodes preferably each have around corner, and a spacing between the electrodes and a spacing betweeneach of the electrodes and the electrolyzing chamber are preferably suchthat lint is prevented from being caught therebetween. Thus, the lint isless liable to adhere onto the electrodes, so that reduction inelectrolysis efficiency due to the lint can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side sectional view of a fully automatic washing machineaccording to one embodiment of the present invention;

FIG. 2 is a partly sectional front view of the fully automatic washingmachine shown in FIG. 1;

FIG. 3 is a partly sectional side view of a water treatment unit;

FIG. 4 is a schematic diagram schematically illustrating theconstruction of the water treatment unit as viewed from the front sidethereof;

FIG. 5 is a plan view of an operation panel for illustrating theconstructions of an operation section and a display section;

FIG. 6 is a diagram illustrating the electrical construction of thefully automatic washing machine according to the embodiment;

FIG. 7 is a flow chart for explaining a washing process in a standardcourse to be performed by the fully automatic washing machine accordingto the embodiment; and

FIG. 8 is a flow chart for explaining a washing process in a zerodetergent course to be performed by the fully automatic washing machineaccording to the embodiment.

EMBODIMENTS OF THE INVENTION

A fully automatic washing machine according to one embodiment of thepresent invention will hereinafter be described with reference to theattached drawings.

FIG. 1 is a side sectional view illustrating the construction of thefully automatic washing machine according to this embodiment. A bottomedcylindrical outer tub 2 is suspended in a forwardly inclined mannerwithin a housing 1 of the washing machine by front suspension rods 3 andrear suspension rods 4 (though one front suspension rod and one rearsuspension rod are shown in the figure, there are two front suspensionrods and two rear suspension rods). A front upper portion of the housing1 projects forward correspondingly to the forward projection of an upperportion of the inclined outer tub 2. The housing 1 has a widely openfront portion 16, which is covered with a detachable front panel 17.Therefore, an upper portion of the front panel 17 projectscorrespondingly to the projection of the upper portion of the outer tub2.

A washing/dehydration tub (inner tub) 5 having a multiplicity ofdehydration perforations formed in a circumferential wall thereof issupported within the outer tub 2 rotatably about a dehydration shaft 6thereof. The outer tub 2 and the inner tub 5 constitute a washing tubaccording to the present invention. A pulsator 7 (water streamgenerating means) for generating water streams for agitation of laundryis disposed on an inner bottom portion of the inner tub 5. A drivingmechanism 10 for driving the pulsator 7 and the inner tub 5 is providedat the bottom of the outer tub 2. The driving mechanism 10 includes thedehydration shaft 6, a pulsator shaft 9 provided in the dehydrationshaft 6 for rotating the pulsator 7, a motor 8 provided coaxially withthe dehydration shaft 6 and the pulsator shaft 9, and a clutch forswitchably transmitting power of the motor 8 only to the pulsator shaft9 or to both the pulsator shaft 9 and the dehydration shaft 6. Thedriving mechanism 10 principally rotates only the pulsator 7 in onedirection or in opposite directions in a washing operation and a rinsingoperation, and unitarily rotates the inner tub 5 and the pulsator 7 inone direction (or in a normal direction) in a dehydrating operation. Theinner tub 5 is rotated once by each turn of the motor 8. On the otherhand, a reduction gear mechanism (not shown) is provided in a middleportion of the pulsator shaft 9, so that the pulsator 7 is rotatedaccording to a reduction radio of the reduction gear mechanism.

A water supply port 11 having a detergent container 11 a for supplying adetergent contained therein is provided on an upper rear side of theouter tub 2. A water supply tube 12 having a water supply valve 13provided in a middle portion thereof is connected to the water supplyport 11. When the water supply valve 13 is opened, tap water is suppliedto the water supply port 11 from an external tap through the watersupply tube 12. Thus, the tap water flows downward into the outer tub 2from the water supply port 11. One end of a water drainage tube 14 isconnected to a front bottom portion or lowermost portion of the outertub 2. The water drainage tube 14 is opened and closed by a waterdrainage valve 15. The other end of the water drainage tube 14 isconnected to an external sewage drain through a self-standing hose notshown. The opening and closing of the water drainage valve 15 areassociated with the switching of the aforesaid clutch. When a torquemotor (not shown in FIG. 1) is not operated, the pulsator 7 is decoupledfrom the inner tub 5 so as to be solely rotated with the water drainagevalve 15 being closed. When the torque motor is operated to pull a wireto the midst, the pulsator 7 is coupled to the inner tub 5 with thewater drainage valve 15 being closed. When the wire is further pulled,the water drainage valve 15 is opened with the pulsator 7 kept coupledto the inner tub 5.

In the washing machine according to this embodiment, the outer tub 2 andthe inner tub 5 are inclined forward as described above, so that opentops of the outer tub 2 and the inner tub 5 are directed forward withrespect to a vertically upward direction. That is, a center line CL ofthe outer tub 2 is tilted at a predetermined tilt angle α with respectto a vertical line VL. Thus, a user standing in front of the washingmachine can easily view the bottom of the inner tub 5 and easily takeout the laundry. A tilt angle α of about 5 degrees to about 20 degreesensures easy take-out of the laundry, and yet suppresses the forwardprojection of the housing 1. In this embodiment, the tilt angle α is setat about 10 degrees.

An electrolyzing device 31 as water treatment means is disposed on alower portion of a circumferential wall of the outer tub 2. Theelectrolyzing device 31 is provided as a unit separate from the outertub 2, and fixed to the outer tub 2 by screws or the like. Theelectrolyzing device 31 is located on a front side of the outer tub 2,and appears when the front panel 17 is removed. This arrangementfacilitates the repair and replacement of the electrolyzing device 31.

The electrolyzing device 31 includes an electrolyzing chamber 32provided separately from the outer tub 2, a pair of electrodes 33disposed in the electrolyzing chamber 32, an upper water communicationpath 34 connecting an upper portion 69 of the electrolyzing chamber 32to the outer tub 2, and a lower water communication path 35 connecting alower portion of the electrolyzing chamber 32 to the outer tub 2.

The pair of electrodes 33 include a first electrode 33 a and a secondelectrode 33 b. The first electrode 33 a and the second electrode 33 beach have a thin square plate shape. The electrolyzing chamber 32 isconfigured in a thin box shape having a smaller depth (indicated by D1in FIG. 3) with respect to the circumferential wall of the outer tub 2.The first electrode 33 a and the second electrode 33 b are disposed inpredetermined spaced relation in the electrolyzing chamber 32 withsurfaces thereof facing toward the circumferential wall of the outertub. This arrangement suppresses the projection of the electrolyzingdevice 31 provided on the circumferential surface of the outer tub 2.Thus, the electrolyzing device 31 is prevented from bumping against thehousing 1 when the outer tub 2 vibrates during the dehydratingoperation.

It is also conceivable that the electrolyzing chamber 32 of theelectrolyzing device 31 is provided integrally with the outer tub 2 andthe electrodes 33 are provided inside the outer tub 2. In this case,however, it is difficult to mount the electrodes 33 in a narrow spaceinside the outer tub 2 and to take out the electrodes 33 for maintenanceand recycling. This is why the electrolyzing device 31 is provided as aunit, i.e., as a water treatment unit 60, which can be mounted outsidethe outer tub 2.

The water treatment unit 60 is constructed so as to be handled unitarilyin the assembling. For example, the water treatment unit has theelectrolyzing chamber 32, the pair of electrodes 33 disposed in theelectrolyzing chamber 32, and the pair of water communication paths 34,35 extending from the electrolyzing chamber 32, so as to solelyconstitute the aforesaid electrolyzing device 31. The electrolyzingchamber 32 and the pair of water communication paths 34, 35 areintegrally formed of a synthetic resin.

The water treatment unit 60 is mounted on a front lower right portion ofthe outer tub 2 as seen from the front side thereof in FIG. 2 in an openspace defined between a corner of the housing 1 and the outer tub 2. Anenergization circuit 30 (see FIG. 6) is electrically connected to thewater treatment unit 60. The energization circuit 30 has a transformer61 and the like. The transformer 61 which typically has a greater weightis stably fixed to a highly strong front portion 62 of a right corner ofthe housing 1 as seen from the front side thereof. The transformer 61may be fixed to the bottom 64 of the outer tub 2. In this case, thevibrations of the outer tub 2 can advantageously be suppressed byutilizing the great weight of the transformer 61.

The water treatment unit 60 and the transformer 61 are located in thevicinity of the open portion 16 of the housing 1 and, therefore, easilyaccessed through the open portion 16 for an assembling operation, amaintenance operation for repair, replacement or the like, and adisassembling operation for recycling. Further, the water treatment unit60 and the transformer 61 are closely located, so that electricalconnection therebetween is easily established. Since the water treatmentunit 60 and the transformer 61 are detachably fixed by screws, theaforesaid operations can advantageously be performed.

The water treatment unit 60 and the transformer 61 are fixed at aposition remote from electrical components for controlling motorrotation such as a rotation sensor 24 (see FIG. 6) provided in the motor8 and a control circuit board 65 fixed to a front left portion 63 of thehousing 1 and including an invertor driving section 23 (see FIG. 6), andinterconnection components (not shown) connecting these components.Thus, noises caused by the transformer 61 during electrolysis can beprevented from exerting an adverse effect on the control of the rotationof the motor 8.

As shown in FIG. 3, the electrodes 33 are disposed parallel to thelargest face, e.g., a front face portion 71, of the thin-box-shapedelectrolyzing chamber 32, and each have a plate shape having a sizecorresponding to the size of the front face portion 71. Since theelectrodes 33 thus have greater areas, a requirement for the surfaceareas is satisfied by a minimum number of electrodes 33. The electrodes33 are formed of a metal, and disposed in opposed relation. Theplate-shaped electrodes 33 are supported at a predeterminedinter-electrode pitch with opposite sides of plate faces thereof oropposite edges thereof being held. Opposite polarities are respectivelyapplied to the pair of electrodes 33 for the electrolysis of the water.

The arrangement of the electrodes 33 is not limited to the pair ofelectrodes having the opposite polarities. For example, three electrodes33 may be disposed in juxtaposition with plate surfaces thereof opposedto each other. Alternatively, five electrodes 33 maybe disposed injuxtaposition with plate surfaces thereof opposed to each other. Inthese cases, the polarities of the electrodes 33 are alternated so thateach adjacent pair of electrodes 33 have opposite polarities. What isimportant is that at least one pair of electrodes 33 are provided.Therefore, the following description is directed to a case where onepair of electrodes 33 are provided.

The vertically opposite edges of the electrodes 33 are held by theelectrolyzing chamber 32. Upper edges of the electrodes 33 are held inrecesses 77 formed in the electrolyzing chamber 32. These recesses 77are defined between a pair of ribs projecting inward from a top faceportion 75 of the electrolyzing chamber 32. Lower edges of theelectrodes 33 are held by a bottom face portion 76 of the electrolyzingchamber 32 via terminal covers 85. The terminal covers 85 cover thelower edges of the electrodes 33, and seal gaps between the bottom faceportion 76 of the electrolyzing chamber 32 and the lower edges of theelectrodes 33 for prevention of accumulation of lint. The electrodes 33may be supported at laterally opposite sides thereof.

The inter-electrode pitch (indicated by D2), more specifically, aspacing (indicated by D3) between the electrodes 33, is preferably notsmaller than 2 mm and not greater than 5 mm, for example. If the spacingis smaller than 2 mm, the lint is liable to come into a space betweenthe electrodes 33 and adhere on the electrodes, thereby reducing theelectrolysis efficiency and the durability. If the spacing is greaterthan 5 mm, application of a higher voltage is required for maintainingthe electrolysis efficiency at a high level, making practicalconstruction difficult. With a spacing of not smaller than 2 mm and notgreater than 5 mm, a practically high durability and a high electrolysisefficiency can be realized.

It is conceivable that the electrolyzing chamber 32 is formed of amaterial different from the material for the outer tub 2 or,alternatively, of the same material as the outer tub 2. In the lattercase, the electrolyzing chamber 32 can easily be handled for recyclingthereof. For example, the electrolyzing chamber 32 is formed of anolefin resin such as polypropylene (PP). This resin is also employed asthe material for the outer tub 2 to impart the outer tub with a chemicalresistance to water containing agents such as a detergent and ableaching agent. Further, addition of a reinforcing material such asglass fibers to the material for the electrolyzing chamber 32advantageously suppresses reduction in the strength of the tub due toincrease in water temperature.

As shown in FIGS. 3 and 4, the electrolyzing chamber 32 has the bottomface portion 76, the front face portion 71, a rear face portion 72, aright side face portion 73 and a left side face portion 74 which extendupright from the periphery of the bottom face portion 76, and the topface portion 75. The electrodes 33 are disposed in a space defined bythe face portions 71 to 76, and water is retained in the space. Theelectrolyzing chamber 32 is configured so as to have a smaller dimensionas measured from the front face portion 71 to the rear face portion 72.The electrodes 33 are disposed generally parallel to the front faceportion 71. The electrolyzing chamber 32 is constituted by a pair ofvertically separable bodies 78, 79 (see FIG. 2).

An upper portion 69 of the electrolyzing chamber 32 is inclined with oneside thereof located at a higher position. That is, the top face portion75 of the electrolyzing chamber 32 is inclined upward toward the rightside thereof as seen from the front side thereof. The upper watercommunication path 34 extends from a part of the rear face portion 72 atthe higher position. The lower water communication path 35 extends froma part of the rear face portion 72 at a lower position of theelectrolyzing chamber 32.

The pair of water communication paths 34, 35 are arranged generallyparallel to each other in vertically juxtaposed relation. The watercommunication paths 34, 35 are tubes having a round section and formedintegrally with the rear face portion 72 of the electrolyzing chamber32. The shape of the pair of water communication paths 34, 35 is notlimited to the tubular shape, as long as spaces are defined therein forcommunication between the inside of the electrolyzing chamber 32 and theinside of the outer tub 2 for water passage. It is also conceivable toprovide the water communication paths separately from the electrolyzingchamber 32 or integrally with the outer tub 2.

The water flows into the electrolyzing chamber 32 from the outer tub 2through the lower water communication path 35. Water treated in theelectrolyzing chamber 32 flows out into the outer tub 2 through theupper water communication path 34. The water is caused to flow in thismanner, for example, by the water streams generated in the outer tub 2by the rotation of the pulsator 7.

The way of the water flow in the pair of water communication paths 34,35 is not particularly limited, but it is also conceivable that thewater flows in a direction opposite to that described above. It ismerely necessary that the pair of water communication paths 34, 35 areprovided for the water inlet and the water outlet, and it is alsoconceivable that at least one of the water communication paths includesa plurality of water communication paths, e.g., three or more watercommunication paths. It is also conceivable that the pair of watercommunication paths are provided unitarily or as a single watercommunication path. For example, the single water communication path isnot divided into two water communication paths for the water inlet andthe water outlet, but may double as a water inlet path and a wateroutlet path. The following description is directed to a case where thelower water communication path 35 and the upper water communication path34 serve as the water inlet path and the water outlet path,respectively.

As shown in FIG. 3, the pair of water communication paths 34, 35 areconnected to the outer tub 2 via packings 81. The packings for the watercommunication paths 34, 35 have the same construction and, therefore, anexplanation will be given only to the packing for the watercommunication path 34.

The packing 81 is a cylindrical elastic component such as composed of arubber. The packing 81 is fitted around the water communication path 34.The packing 81 is press-fitted in a connection port 67 formed on anouter surface 66 (circumferential wall) of the outer tub 2 externally ofthe outer tub 2. The packing 81 has a long sealing distance between thetubular water communication path 34 and the connection port 67. Thepacking 81 is fitted in a predetermined radially compressed manner toseal a gap between the inner circumference of the connection port 67 andthe outer circumference of the water communication path 34. The packing81 is elastically deformable in its radial and axial directions. Thus,the packing 81 accommodates dimensional errors in the connection port 67and the water communication path 34. Further, the packing 81 canaccommodate a dimensional difference between a pitch of the pair ofwater communication paths 34, 35 and a pitch of the pair of connectionports 67. The packing 81 accommodates thermal deformation of the outertub 2 occurring when hot water is retained in the outer tub 2. Thus,breakage and water leakage can be prevented.

Besides the cylindrical packing, an O-ring and a sheet packing may beemployed as the packing 81.

The electrolyzing chamber 32 has a plurality of fixing portions, e.g.,four fixing portions 80, provided in the vicinity of the pair of watercommunication paths 34, 35 for fixing the electrolyzing chamber 32 tothe outer tub 2 by screws. The screws 86 extending through through-holesof the fixing portions 80 are externally screwed into bosses 68projecting from the outer surface 66 of the outer tub 2.

Terminals 84 of the electrodes 33 extend outward through the bottom faceportion 76 of the electrolyzing chamber 32 as shown in FIG. 4. Even ifwater drops adhere on the outer surface of the electrolyzing chamber 32due to water condensation and overflow of the water from the washingtub, a short-circuit between the terminals 84 of the pair of electrodes33 is less liable to occur due to the water drops. Thus, the terminals84 can electrically be isolated from each other. Further, a separationplate 87 is provided for separating the terminals 84 of the pair ofelectrodes 33 from each other. The separation plate 87 prevents movementof the water drops to ensure the electrical isolation. The separationplate 87 may double as the fixing portion 80 formed integrally with theelectrolyzing chamber 32 for reduction of the number of the components.

The water treatment unit 60 is assembled in the following manner. Withthe separable bodies 78, 79 of the electrolyzing chamber 32 beingseparated from each other, the electrodes 33 are set in one 78 of theseparable bodies. Then, the pair of separable bodies 78, 79 are combinedwith each other, and seams thereof are sealed. Thus, the assembling ofthe water treatment unit 60 is completed. The water treatment unit 60having the box-shaped electrolyzing chamber 32 per se can be tested, forexample, for the sealing property and the electrolysis performancethereof, before it is mounted on the outer tub 2. Then, the pair ofwater communication paths 34, 35 are externally press-fitted in theconnection ports 67 of the outer tub 2 with the intervention of thepackings 81. The fixing portions 80 of the electrolyzing chamber 32 arerespectively fixed to the bosses 68 of the outer tub 2 by screws. Theterminals 84 of the electrodes 33 are electrically connected to theenergization circuit 30. Further, the water treatment unit 60 can beremoved from the outer tub 2 by performing the aforesaid operations in areverse order. Thus, the maintenance operation and the disassemblingoperation for the recycling can be facilitated.

Since the water treatment unit 60 is thus provided on the outside of theouter tub 2, the mounting operation for mounting the water treatmentunit 60 on the outer tub 2, the maintenance operation for the watertreatment unit 60 and the disassembling operation for the recycling caneasily be performed from the outside of the outer tub 2. If theelectrodes 33 were disposed between the outer tub 2 and the inner tub 5,there would be a need for an additional space in the outer tub 2 andadditional water to be retained in the space. Where the water treatmentunit 60 is mounted on the outer surface of the outer tub 2, on the otherhand, the need for the additional space and the additional water isobviated.

It is herein merely necessary that the water treatment unit 60 whichensures easy implementation of the aforesaid operations is provided as aunit separate from the outer tub 2 and unitarily handled. For example,the water treatment unit 60 may include the pair of electrodes 33 andthe fixing portions 80 for fixing the unit to the outer tub 2, and beadapted to electrolyze the water in use for the washing process by itsown or in cooperation with the outer tub 2 to impart the water with acleaning capability without addition of the detergent.

The water treatment unit 60 is detachable from the outer tub 2, so thatthe detaching operation can highly conveniently be performed. Where theelectrodes 33 contain a precious metal, easy recycling is advantageouslyensured.

Since the water treatment unit 60 incorporates the electrolyzing chamber32 and the pair of electrodes 33, the water treatment unit 60 canunitarily be handled for the mounting and maintenance operations. Thus,these operations can further be facilitated.

Since the electrodes 33 are supported at the opposite sides thereofwithin the box-shaped electrolyzing chamber 32, the water treatment unit60 can be handled without careful attention. Therefore, the assembling,maintenance and disassembling operations can further be facilitated. Inaddition, there is no possibility that the electrodes 33 are displacedor dislodged in the electrolyzing chamber 32 due to the vibrations ofthe outer tub 2 during the dehydrating operation.

With the packings 81 provided between the water treatment unit 60 andthe outer tub 2, dimensional errors in the outer tub 2 and thecorresponding portion of the water treatment unit 60 can be accommodatedby elastic deformation of the packings 81 when the water treatment unit60 is mounted on the outer tub 2, so that the mounting can easily beachieved. In addition, the sealing of the gap between the watertreatment unit 60 and the outer tub 2 can be achieved. Therefore,bonding for the sealing can be obviated, so that labor for theassembling operation can be alleviated and the detaching anddisassembling operations can be facilitated.

By the provision of the pair of water communication paths 34, 35, thewater inlet path and the water outlet path between the electrolyzingchamber 32 and the outer tub 2 can be separated, whereby the water iscaused to efficiently flow between the electrolyzing chamber 32 and theouter tub 2. Thus, the treated water can be supplied into the outer tub2 for effective use in the washing process without wastage, so that thecleaning capability and the sterilizing capability can be enhanced.Further, the water from the outer tub 2 is caused to flow within theelectrolyzing chamber 32 for efficient electrolysis.

The pair of water communication paths 34, 35 are spaced apart from eachother, so that the treated water is prevented from flowing back into theelectrolyzing chamber 32 immediately after flowing out of theelectrolyzing chamber 32.

The pair of water communication paths 34, 35 are provided at differentvertical positions of the thin-box-shaped electrolyzing chamber. 32provided on the outer surface 66 of the outer tub 2, so that thestagnation of the water and the trapping of air can be suppressed. Thus,the water is caused to flow vertically (in a direction indicated by anarrow in FIG. 3) for efficient electrolysis.

Where the water flows upward in the electrolyzing chamber 32, theprovision of the upper water communication path 34 at the inclined upperportion 69 of the electrolyzing chamber 32 permits the water flowingupward in the electrolyzing chamber 32 to be guided along theinclination into the upper water communication path 34 to speedily flowout, thereby facilitating the water flow. The lower water communicationpath 35 provided at the lower end of the electrolyzing chamber 32prevents the stagnation of the water in the electrolyzing chamber 32.This advantageously facilitates the water flow in the electrolyzingchamber 32.

It is preferred that the electrodes 33 are thus provided in a spacewhere the water flows to ensure efficient electrolysis. It isparticularly preferred that the electrodes 33 are provided in a spacewhere the water is circulated with respect to the outer tub 2. Thus, theuse efficiency of the electrolyzed water can be enhanced. For example,it is conceivable that a circulation mechanism is provided for forciblycirculating the water by sucking the water from the outer tub 2 throughan inlet thereof and discharging the water through an outlet thereof,and the electrodes 33 are provided in the circulation mechanism. Thecirculation mechanism may comprise a tubular water passage for watercommunication between an upper portion and a lower portion of the outertub 2, and an electric pump for causing the water to pass through thewater passage. The construction of such a circulation mechanism isdisclosed in Japanese Patent Application No. 2000-196894 and the likefiled by the applicant of the present invention. Besides, a knownconstruction for the water circulation may be employed.

Since the electrolyzing chamber 32 has a thin box shape having a smallerdepth with respect to the outer surface of the outer tub 2, theprojection of the water treatment unit 60 from the outer surface of theouter tub 2 can be reduced. Where the electrolyzing chamber 32 is of athin type fitted on the outer side surface 66 as the outer surface ofthe outer tub 2, for example, an increase in the size of the housing 1is suppressed which may be required for prevention of the bump of thewater treatment unit 60 against the housing 1 during the dehydratingoperation as described above. Thus, space saving can be achieved. Wherethe electrolyzing chamber 32 is of a thin type fitted on the bottom 64as the outer surface of the outer tub 2, the piping arrangement for thedrainage of used water from the electrolyzing chamber 32 can besimplified, thereby achieving space saving.

Where the electrolyzing chamber 32 is provided below the outer tub 2,e.g., below the bottom 64 and the outer side surface 66, water retainedat a lower water level within the outer tub 2 can also be utilized. Forexample, the electrolyzing process can be started in the midst of thewater supply to the outer tub 2, so that the time required for theelectrolysis can be reduced. Further, a course in which the electrolyzedwater is utilized at a lower water level can be realized.

Where the electrolyzing chamber 32 is provided on the outer side surface66 of the outer tub 2 and the water communication path 35 is provided atthe lower end of the electrolyzing chamber 32, the water in theelectrolyzing chamber 32 is allowed to flow out into the outer tub 2through the water communication path 35 during the water drainage fromthe outer tub 2.

It is also conceivable that at least a part of the electrolyzing chamber32 is formed integrally with the outer tub 2. In this case, theelectrolyzing chamber 32 is preferably provided so as to project outwardfrom the outer surface of the outer tub 2 or to be recessed along theinner surface of the outer tub 2. Thus, the interior configuration ofthe outer tub 2 can generally properly be maintained, thereby preventingreduction in space efficiency within the outer tub 2 and increase inwater consumption more than necessary. Where the inner surface of theelectrolyzing chamber 32 and the inner surface of the outer tub 2 arecontinuous, these inner surfaces are preferably inclined with respect toeach other to facilitate the water flow between the inside of the outertub 2 and the inside of the electrolyzing chamber 32.

In the meantime, the water from the outer tub 2 is often contaminatedwith lint. If the lint adheres on the electrodes 33, there is a fearthat the durability of the electrodes 33 and the electrolysis efficiencyare reduced. Therefore, a problem associated with the lint entering intothe water treatment unit 60 is solved in the following manner.

Corner portions 82 of the electrodes 33 each have an R-shape 83 (partlyshown in FIG. 4). Thus, the electrodes 33 have no corner edge, so thatthe lint is less liable to be caught on the corner portions of theelectrodes 33 and easily released. Even if the lint is caught on thecorner portions 82, the lint is naturally released from the cornerportion 82 by the water streams.

The R-shape 83 includes an R-shape as seen perpendicularly to the platesurface of the electrode 33, and an R-shape as seen along the platesurface of the electrode 33. At least some of the corner portions mayberounded, but it is preferred that more of the corner portions,particularly, all the corner portions, are rounded.

The spacing (D3) between the electrodes 33 is determined so as toprevent the lint from being caught therebetween. The spacing ispreferably not smaller than 2 mm, for example. If the spacing is smallerthan 2 mm, the lint is liable to be caught. Further, a spacing (D4)between the electrode 33 and the electrolyzing chamber 32 may be thesame as the aforesaid spacing, or zero. That is, there may be no gapbetween the electrodes and the electrolyzing chamber 32.

This prevents reduction in water fluidity due to adhesion of the lint.This also prevents the lint from hindering the contact of the water withthe electrodes 33. As a result, the reduction in electrolysis efficiencydue to the lint can be prevented, so that the electrolysis efficiencycan be maintained at a higher level. Since the lint is permitted toenter the water treatment unit 60, there is no need for provision of alint filter and maintenance against the lint.

As shown in FIG. 2, the washing machine may have an air bubble generator88 for generating air bubbles from the bottom 64 of the outer tub 2 forenhancement of the cleaning capability. Where the air bubble generator88 and the water treatment unit 60 are used in combination, theelectrolysis can be achieved more efficiently.

The air bubble generator 88 includes an air pump 89, an air hose 90connected to an air outlet of the air pump 89 for air supply, and anozzle (not shown) connected to an end of the air hose 90 for ejectingair into the outer tub 2. When the air bubble generator 88 is actuatedin the washing process, the air is ejected from the nozzle, and flowsinto the inner tub 5 through the perforations of the inner tub 5 togenerate air bubbles below the pulsator 7. The air bubbles are agitatedby the rotating pulsator 7, and broken into a multiplicity of minute airbubbles. When the minute air bubbles are brought into contact with thelaundry, the minute air bubbles are broken to generate ultrasonic waves.At this time, shock waves within an ultrasonic range are generated,thereby promoting removal of dirt components adhering onto the laundry.Thus, the cleaning capability can be enhanced as compared with a casewhere air bubbles are not applied.

The air bubble generator 88 has a function as air supplying means forsupplying air into the electrolyzing chamber 32 from a lower portion 70of the electrolyzing chamber 32 in addition to the originally intendedfunction for enhancing the cleaning capability. The air supplying meansgenerates water streams by promoting upward water flow within theelectrolyzing chamber 32 of the water treatment unit 60. The air hose 90is branched in a middle portion thereof. One branch extends to thenozzle, and the other branch is connected to the electrolyzing chamber32.

A single air supply port 91 is provided in the lower portion 70 of theelectrolyzing chamber 32 so as to be supplied with the air from the airhose 90 as shown in FIG. 4. A plurality of air supply ports 91 maybeprovided. The air pump 89 is actuated in the electrolyzing process. Theair supplied into the electrolyzing chamber 32 from the air supply port91 is broken into air bubbles E, which float in the electrolyzingchamber 32 to flow into the outer tub 2 through the upper watercommunication path 34 (in a direction indicated by a one-dot-and-dashline in FIG. 4). Correspondingly, the water retained in theelectrolyzing chamber 32 is caused to flow by the flow of the air (in adirection indicated by a broken line in FIG. 4). Particularly, where theupper portion 69 of the electrolyzing chamber 32 is inclined and thewater communication path 34 is located at the higher position, the airbubbles can quickly flow out of the electrolyzing chamber 32, so thatthe water flow can further be facilitated. There is no possibility thatthe air bubbles are trapped between the electrodes 33. As a result, theelectrolysis efficiency can be enhanced. Therefore, a voltage requiredto provide a predetermined electrolyzing capability can be reduced,thereby realizing reduction in size, cost and power consumption of theelectrical components such as the transformer 61.

The air supply port 91 is disposed so as not to overlap with theelectrodes 33 as seen in plan and so as not to face toward theelectrodes 33. Thus, the air can be supplied without contact with theelectrodes 33. Therefore, reduction in electrolysis efficiency due tothe air can be suppressed. It is preferred that the air supply port 91is horizontally spaced a predetermined distance from edges of theelectrodes 33 in a corner of the bottom face portion 76 of theelectrolyzing chamber 32. The predetermined distance is a distance suchas not to permit the contact of the air with the electrodes 33, forexample, 10 mm.

The air supply port 91 and the upper water communication path 34 aredisposed at diagonally opposite positions as seen from the front side.Thus, the air can flow a longer distance in the electrolyzing chamber32, so that the water flow can be facilitated. The air supply port 91and the lower water communication path 35 are disposed at laterallyseparate positions as seen from the front side. Thus, water present in aposition remote from the lower water communication path 35 is caused toeasily flow, which may otherwise have a difficulty in flowing.

Thus, the water flow in the electrolyzing chamber 32 can be facilitatedfor efficient electrolysis. In addition, the air is introduced into theouter tub 2 for improvement of the cleaning capability. The aforesaidair pump 89 may be adapted to supply the air only to the electrolyzingchamber 32. Referring back to FIG. 1, the following explanation isdirected to a case where the air bubble generator 88 is not provided.

A top plate 18 is provided on a top face of the housing 1. The top plate18 has a laundry loading port 18 a provided in a center portion thereof.The loading port 18 a is covered with an openable upper lid 19. Anoperation panel 48 is provided in front of the top plate 18.

FIG. 5 is a plan view of the operation panel 48. The operation panel 48includes an operation section 21 and a display section 28. The operationsection 21 has a power supply key 49 for turning on power supply to themachine, a start key 36 for starting a washing process, and a set ofcourse keys 37 (selecting means) for selecting a washing course. Thecourse key set 37 includes a standard course key 38 for selecting astandard course, a self-arranged course key 39 for selecting aself-arranged course, a fast course key 40 for selecting a fast course,a thorough rinsing course key 41 for selecting a thorough rinsingcourse, and a zero detergent course key 42 for selecting a zerodetergent course.

The standard course is a washing course in which a standard washingprocess is performed. The self-arranged course is a washing course inwhich a washing process is performed according to a procedure set by auser (manually set procedure). The fast course is a washing course inwhich a washing process time is short. The thorough rinsing course is awashing course in which a rinsing operation is thoroughly performed byincreasing a rinsing operation period and the number of times of therinsing operation. These courses employ a detergent. In these courses,water containing the detergent (detergent solution) is retained in theouter tub 2 and the laundry is washed by generating water streams by therotation of the pulsator 7. These courses are collectively referred toas a first washing course.

The zero detergent course employs no detergent. In this course, waterretained in the outer tub 2 is electrolyzed by the electrolyzing device31 for production of electrolyzed water, and the laundry is washed bygenerating water streams by the rotation of the pulsator 7. The zerodetergent course is referred to as a second washing course.

The display section 28 includes a course display section 43 fordisplaying a selected washing course, a detergent amount display section44 (information means) for displaying the amount of the detergentcorresponding to the load of the laundry, and a zero detergent displaysection 45 (second information means) for indicating addition of nodetergent by lighting an LED. In the course display section 43, LEDs 46are provided in the vicinity of the respective course keys, and one ofthe LEDs corresponding to the selected washing course is lighted. In thedetergent amount display section 44, a plurality of LEDs 47 are providedin an illustration of a detergent measure cup, and a number of LEDs 47corresponding to the amount of the detergent are lighted for indicationof the detergent amount.

FIG. 6 is a diagram illustrating the electrical construction of thefully automatic washing machine according to this embodiment. A controlcenter is a control section 20 including a CPU, a RAM, a ROM, a timerand the like. The control section 20 is comprised of a microprocessor.An operation signal is inputted to the control section 20 from theoperation section 21. A water level detection signal is inputted to thecontrol section from a water level sensor 22 for detecting the level ofthe water contained in the outer tub 2. The control section 20 controlsthe rotation of the motor 8 via the invertor driving section 23, andcontrols the operation of the torque motor 26 and the operation of thewater supply valve 13 via a load driving section 25. The torque motor 26controls the operation of the clutch 27 and the operation of the waterdrainage valve 15 as described above. Further, the control section 20controls the operation of the display section 28 and the operation of abuzzer 29 for notifying the end of the process and an abnormality in theprocess. The motor 8 is provided with a rotation sensor 24 foroutputting pulse signals according to the rotation thereof, and thepulse signals are inputted to the control section 20. The rotationsensor 24 is provided for detecting the rotation speed of the motor 8,i.e., the rotation speed of the inner tub 5.

The pair of electrodes 33 are connected to an output side of the controlsection 20 via the energization circuit 30 including the transformer 61and the like. When an energization signal is outputted from the controlsection 20, the energization circuit 30 is actuated for energization ofthe pair of electrodes 33.

Sequences for the respective washing courses are stored in the ROM 20 aof the control section 20.

When a washing course is selected by the operation of the course key set37, a sequence for the selected washing course is read out of the ROM 20a. Then, the control section 20 controls loads to be applied to themotor 8 and the like according to the sequence, and performs the washingprocess according to the selected washing course.

An explanation will be given to the operation of the fully automaticwashing machine having the aforesaid construction according to thisembodiment. With reference to a flow chart in FIG. 7, there will firstbe described a case where a user selects the standard course which is atypical washing course employing a detergent.

When the start key 36 is pressed to provide a command for the start ofthe washing process, the load or the amount of laundry loaded in theinner tub 5 is detected prior to the supply of water (Step S1). Morespecifically, the pulsator 7 is rotated for a short period of time, andthe load is determined on the basis of a period during which theconsequent inertial rotation continues. In this case, load detectionmeans is constituted by the pulsator 7 and the control section 20. Ofcourse, the detection of the load is not limited to this method, but anyother method may be employed.

Next, a washing water level is determined according to the detected load(Step S2), and a detergent amount corresponding to the load is displayedon the detergent amount display section 44 (Step S3). In view of thedisplay in the detergent amount display section 44, a user adds a properamount of a detergent into the inner tub 5.

In turn, the supply of tap water is started, and the water is suppliedto the determined washing water level (Steps S4 to S6). Thus, adetergent solution obtained by dissolving the detergent in the tap wateris contained in the outer tub 2.

Subsequently, the pulsator 7 is rotated at a predetermined speed in onedirection or in opposite directions, whereby water streams are generatedin the outer tub 2 for washing the laundry (Step S7). Dirt adhering tothe laundry is removed by the effects of the detergent and the waterstreams. After a lapse of a predetermined washing period, the pulsator 7is stopped to end the washing operation (Steps S8, S9).

After the washing operation is completed, a first intermediatedehydrating operation, a first rinsing operation, a second intermediatedehydrating operation, a second rinsing operation and a finaldehydrating operation are sequentially performed. Thus, the washingprocess is completed.

With reference to a flow chart in FIG. 8, an explanation will be givento a case where the user selects the zero detergent course which employsno detergent.

When the start key 36 is pressed to provide a command for the start ofthe washing process, the LED of the zero detergent display section 45 islighted instead of the display in the detergent amount display section44 (Step S11). Thus, the user is notified that no detergent is added.

Then, the supply of tap water is started (Step S12) The water issupplied to a predetermined washing water level (more specifically alower water level) for the zero detergent course. When the water levelin the outer tub 2 reaches a predetermined level which is lower than thewashing water level and permits the pair of electrodes 33 of theelectrolyzing device 31 to be submerged in the water, the electrolyzingdevice 31 is actuated, i.e., the pair of electrodes are energized (StepsS13, S14). Further, the pulsator 7 is rotated at a predetermined speedin one direction or in opposite directions to generate water streams inthe outer tub 2 (Step S15).

The tap water contains very small amounts of impurities such as iron,calcium, magnesium and chlorine. Therefore, electrolyzed water isproduced through the electrolyzing process performed in theelectrolyzing chamber 32, and the tap water goes back and forth betweenthe electrolyzing chamber 32 and the outer tub 2, whereby the outer tub2 is gradually filled with the electrolyzed water. The electrolyzedwater has a weak alkalinity. Further, active oxygen as well ashypochlorous acid (HClO) and hypochlorous ions (ClO—) are generated inthe electrolyzed water in the electrolyzing chamber 32. Together withthe electrolyzed water, hypochlorous acid and hypochlorous ions flowinto the outer tub 2. In the outer tub 2, dirt adhering to the laundryis removed by the effect of the alkaline water and the effect of thewater streams. Further, the laundry is sterilized by the effect ofhypochlorous acid and hypochlorous ions. The dirt removed from thelaundry is decomposed by the effect of the active oxygen in theelectrolyzing chamber 32, and prevented from adhering again to thelaundry.

When the water reaches the washing water level, the water supply isstopped (Steps S16, S17). On the other hand, the operation of theelectrolyzing device 31 and the operation of the pulsator 7 arecontinued. After a lapse of a predetermined washing period, theoperation of the electrolyzing device 31 (the energization of the pairof electrodes 33) is stopped, and the pulsator 7 is stopped forcompletion of the first washing operation (Steps S18 to S20).

After an intermediate dehydrating operation is performed, a secondwashing operation is performed in the same manner as the first washingoperation. Upon completion of the second washing operation, a finaldehydrating operation is performed. Thus, the washing process in thezero detergent course is completed.

In the washing course employing the detergent, e.g., in the standardcourse, the electrolyzing device 31 may be operated in the rinsingoperations (first and second rinsing operations), so that theelectrolyzed water is employed for rinsing the laundry. Thus, thelaundry can be sterilized while being rinsed.

An automatic detergent adding device (adding means) may be provided forautomatically adding a proper amount of the detergent according to thedetected load. Thus, the detergent is automatically added in the washingcourse employing the detergent, e.g., in the standard course, and nodetergent is added in the zero detergent course. A conventionally knowndevice may be used as the automatic detergent adding device and,therefore, no explanation will be given to the construction thereof.

While the embodiment of the present invention has thus been described,it should be understood that the invention be not limited to theabove-described embodiment as will be described below.

The washing machine according to the present invention is not limited tothe fully automatic washing machine. The invention is applicable to aso-called drum type washing machine in which the washing tub isconstituted by an outer tub and a drum of horizontal axis type providedin the outer tub. Further, the invention is applicable to a so-calleddouble tub washing machine in which a single washing tub is providedseparately from a dehydration tub.

The water treatment means according to the present invention is notlimited to the electrolyzing device, but any treatment means may beemployed which performs a specific treatment on tap water to impart thetap water with the cleaning capability. Further, the present inventionis not limited to the electrolysis of the tap water alone. For promotionof the electrolysis of the tap water, the electrolyzing process may beperformed on an electrolytic solution prepared by adding salt or sodiumhydrogencarbonate to the tap water.

The water stream generating means according to the present invention isnot limited to the pulsator. For example, the water streams may begenerated by rotating the inner tub. In this case, the inner tub servesas the water stream generating means. What is important is that thewater stream generating means is capable of generating water streamswithin the washing tub.

The information means and the second information means according to thepresent invention are not limited to the display means such as thedetergent amount display section and the zero detergent display section.For example, means for notifying the amount of the detergent and thenon-addition of the detergent by voice may be employed.

It should be understood that the present invention be not limited to theembodiment described above, but various modifications may be made withinthe scope of the present invention as defined by the appended claims.

This application claims priority benefits under the Convention on thebasis of Japanese Patent Applications No. 2001-106923 and No.2001-133254 filed with the Japanese Patent Office on Apr. 5, 2001 and onApr. 27, 2001, respectively, the disclosure thereof being incorporatedherein by reference.

1. An electric washing machine comprising: a washing tub to containlaundry; water motion generating means to generate water motion in thewashing tub; water treatment means to perform a specific treatment ontap water to be supplied into the washing tub or tap water supplied intothe washing tub to impart the water with a cleaning capability withoutaddition of a detergent; storage means which stores therein a sequencefor a first washing course in which the laundry is washed by generatingwater motion in the washing tub which contains a detergent solutionprepared by adding the detergent into the tap water, and a sequence fora second washing course in which the laundry is washed without the useof the detergent by generating water motion in the washing tub whichcontains a cleaning liquid imparted with the cleaning capability bytreating the tap water by the water treatment means; selecting means toallow a user to select the first washing course or the second washingcourse; control means to control operations of the water motiongenerating means and the water treatment means on the basis of thesequence for the washing course selected by the selecting means toperform a washing process in the selected washing course; load detectingmeans to detect a load of the laundry; and information means to notify adetergent amount according to the load detected by the load detectingmeans, wherein the control means actuates the load detecting means ofthe detection of the load and causes the information means to notify thedetergent amount according to the detected load in the washing processof the first washing course, and prohibits the information means fromnotifying the detergent amount in the washing process of the secondwashing course.
 2. An electric washing machine as set forth in claim 1,wherein the water treatment means comprises a pair of electrodes forelectrolysis of the tap water, and produces the cleaning liquid byelectrolyzing the tap water through energization of the pair ofelectrodes.
 3. An electric washing machine as set forth in claim 1,further comprising: second information means to notify that no detergentis added, wherein the control means actuates the second informationmeans in the washing process of the second washing course.
 4. Anelectric washing machine as set forth in claim 3, wherein the watertreatment means comprises a pair of electrodes for electrolysis of thetap water, and produces the cleaning liquid by electrolyzing the tapwater through energization of the pair of electrodes.
 5. An electricwashing machine comprising: a washing tub to contain laundry; watermotion generating means to generate water motion in the washing tub;water treatment means to perform a specific treatment on tap water to besupplied into the washing tub or tap water supplied into the washing tubto impart the water with a cleaning capability without addition of adetergent; storage means which stores therein a sequence for a firstwashing course in which the laundry is washed by generating water motionin the washing tub which contains a detergent solution prepared byadding the detergent into the tap water, and a sequence for a secondwashing course in which the laundry is washed without the use of thedetergent by generating water motion in the washing tub which contains acleaning liquid imparted with the cleaning capability by treating thetap water by the water treatment means; selecting means to allow a userto select the first washing course or the second washing course; controlmeans to control operations of the water motion generating means and thewater treatment means on the basis of the sequence for the washingcourse selected by the selecting means to perform a washing process inthe selected washing course; load detecting means to detect a load ofthe laundry; and adding means to add the detergent in an amountaccording to the load detected by the load detecting means, wherein thecontrol means actuates the load detecting means to detect the load andcauses the adding means to add the detergent in the amount according tothe detected load in the washing process of the first washing course,and prohibits the adding means from adding the detergent in the washingprocess of the second washing course.
 6. An electric washing machine asset forth in claim 5, wherein the water treatment means comprises a pairof electrodes for electrolysis of the tap water, and produces thecleaning liquid by electrolyzing the tap water through energization ofthe pair of electrodes.